So called “solid ink” printers encompass various imaging devices, including printers and multi-function platforms and offer many advantages over many other types of high speed or high output document reproduction technologies such as laser and aqueous inkjet approaches. These often include higher document throughput (i.e., the number of documents reproduced over a unit of time), fewer mechanical components needed in the actual image transfer process, fewer consumables to replace, sharper images, as well as being more environmentally friendly (far less packaging waste).
A schematic diagram for a typical solid ink imaging device is illustrated in FIG. 1. The solid ink imaging device, hereafter simply referred to as a printer 100 has an ink loader 110 which receives and stages ink sticks which remain in solid form at room temperatures. The ink stock can be refilled by a user by simply adding more ink as needed to the ink loader 110. Separate loader channels are used for the different colors. For, example, only black ink is needed for monochrome printing, while ink colors of black, cyan, yellow and magenta are typically needed for color printing. Each color is loaded and fed in independent channels of the ink loader.
An ink melt unit 120 melts the ink by raising the temperature of the ink sufficiently above its melting point. During a melting phase of operation, the leading end of an ink stick contacts a melt plate or heated surface of the melt unit and the ink is melted in that region. The liquefied ink is supplied to a single or group of print heads 130 by gravity, pump action, or both. In accordance with the image to be reproduced, and under the control of a printer controller (not shown), a rotating print drum 140 receives ink droplets representing the image pixels to be transferred to paper or other media 170 from a sheet feeder 160. To facilitate the image transfer process, a pressure roller 150 presses the media 170 against the print drum 140, whereby the ink is transferred from the print drum to the media. The temperature of the ink can be carefully regulated so that the ink fully solidifies just after the image transfer.
While there may be advantages to the use of solid ink printers compared to other image reproduction technologies, high speed and voluminous printing sometimes creates problems not satisfactorily addressed by the prior art solid ink printing architectures. To meet the large ink volume requirement, ink loaders must have large storage capacity and be able to be replenished by loading ink at any time the loader has capacity for additional ink.
In typical prior art ink chuck or stick reservoirs, the sticks are positioned end to end in straight or linear channel or chute with a melt head on one end and a spring biased push stick on the other end. As these solid ink printers have high productivity rates, the storage of ample supplies of ink is very desirable. As the space in solid ink printers is limited, finding a location within the printer to accommodate a long straight chute for holding an ample supply of ink is a challenge. The amount of ink that can be accommodated is limited by the physical dimensions of the printer and can not be greater that the amount accommodated by a linear chute diagonally positioned in the printer.
To assure that the proper ink stick is inserted into a printer, the ink sticks may have an irregular shape which provides a key for moving the sticks by a corresponding key formed in the loading position of the printer. Since the ink sticks have this keying feature, once the ink stick has passed through the closely matched keyed opening, the ink sticks may not be retrieved easily. The planar keying surface is above the top of the ink when the ink is fully inserted. Removal of the ink stick when necessary requires the use of a tool or sharp object which must be impaled into the top surface of the ink stick. The impaling of the ink stick may create an issue when later trying to use the stick as it may crack or shed material. Further, the tool or object may not be readily available for the user and the user may not be aware of such a procedure to remove the ink stick.